MAGEMinApp
Effortlessly compute phase diagrams and Pressure-Temperature paths
A set of tools to compute phase equilibria for Earth-like compositions

MAGEMin is a Gibbs energy minimization solver, which computes the thermodynamically most stable assemblage for a given thermodynamic database and a set of bulk-rock composition, pressure and temperature conditions. It returns the fraction of the stable minerals, their compositions and all thermodynamically-derived parameters such as density, thermal expansivity, heat capacity etc.
MAGEMin backend is written as a parallel C library and uses a combination of linear programming, the extended Partitioning Gibbs free Energy approach and gradient-based local minimization to compute the most stable mineral assemblage. In this, it differs from existing approaches which makes it particularly suitable to utilize modern multicore processors.
While MAGEMin is the engine for the prediction of the stable phases, it is best used with the Julia interface MAGEMin_C and/or the web-browser julia MAGEMinApp.

Note
Please keep in mind that the datasets are only calibrated for a limited range of P,T and bulk rock conditions. If you go too far outside those ranges, MAGEMin (or most other thermodynamic software packages for that matter) may not converge or give bogus results. Developing new, more widely applicable, thermodynamic datasets is a huge research topic, which will require funding to develop the models themselves, as well as to perform targeted experiments to calibrate those models.
An open-access paper describing the methodology is published in G-cubed:
Development of this software package was funded by the European Research Council under grant ERC CoG #771143 - MAGMA, and is currently supported by German Research Foundation (DFG) - Project number #521637679
Green, E.C.R., Holland, T.J.B., Powell, R., Weller, O.M., & Riel, N. (2025). Journal of Petrology, 66. doi: 10.1093/petrology/egae079
Weller, O.M., Holland, T.J.B., Soderman, C.R., Green, E.C.R., Powell, R., Beard, C.D., & Riel, N. (2024). New Thermodynamic Models for Anhydrous Alkaline-Silicate Magmatic Systems. Journal of Petrology, 65. doi: 10.1093/petrology/egae098
Holland, T.J.B., Green, E.C.R., & Powell, R. (2022). A thermodynamic model for feldspars in KAlSi₃O₈-NaAlSi₃O₈-CaAl₂Si₂O₈ for mineral equilibrium calculations. Journal of Metamorphic Geology, 40, 587-600. doi: 10.1111/jmg.12639
Tomlinson, E.L., & Holland, T.J.B. (2021). A Thermodynamic Model for the Subsolidus Evolution and Melting of Peridotite. Journal of Petrology, 62. doi: 10.1093/petrology/egab012
Holland, T.J.B., Green, E.C.R., & Powell, R. (2018). Melting of Peridotites through to Granites: A Simple Thermodynamic Model in the System KNCFMASHTOCr. Journal of Petrology, 59, 881-900. doi: 10.1093/petrology/egy048
Green, E.C.R., White, R.W., Diener, J.F.A., Powell, R., Holland, T.J.B., & Palin, R.M. (2016). Activity-composition relations for the calculation of partial melting equilibria in metabasic rocks. Journal of Metamorphic Geology, 34, 845-869. doi: 10.1111/jmg12211
White, R.W., Powell, R., Holland, T.J.B., Johnson, T.E., & Green, E.C.R. (2014). New mineral activity-composition relations for thermodynamic calculations in metapelitic systems. Journal of Metamorphic Geology, 32, 261-286. doi: 10.1111/jmg.12071
Holland, T.J.B., & Powell, R.W. (2011). An improved and extended internally consistent thermodynamic dataset for phases of petrological interest, involving a new equation of state for solids. Journal of Metamorphic Geology, 29, 333-383. doi: 10.1111/j.1525-1314.2010.00923.x
Stixrude, L., & Lithgow-Bertelloni, C. (2011). Thermodynamics of mantle minerals - II. Phase equilibria. Geophysical Journal International, 184, 1456-1475. doi: 10.1111/j.1365-246X.2010.04890.x
Stixrude, L., & Lithgow-Bertelloni, C. (2021). Thermal expansivity, heat capacity and isothermal compressibility of the mantle. Geophysical Journal International, 228, 1296-1314. doi: 10.1093/gji/ggab394
Stixrude, L., & Lithgow-Bertelloni, C. (2024). Thermodynamics of mantle minerals – III: the role of iron. Geophysical Journal International, 237(3), 1699-1733. doi: 10.1093/gji/ggae126
Evans, K.A., & Frost, B.R. (2021). Deserpentinization in Subduction Zones as a Source of Oxidation in Arcs: a Reality Check. Journal of Petrology, 62(3), egab016. doi: 10.1093/petrology/egab016
Diener, J.F.A., Powell, R., White, R.W., & Holland, T.J.B. (2007). A new thermodynamic model for clino- and orthoamphiboles in the system Na₂O-CaO-FeO-MgO-Al₂O₃-SiO₂-H₂O-O. Journal of Metamorphic Geology, 25, 631-656.
Rebay, G., Powell, R., & Diener, J.F.A. (2022). New activities for the system FeO-MgO-Al₂O₃-SiO₂ with applications to metamorphic rocks. Journal of Metamorphic Geology.
Franzolin, E., Schmidt, M.W., & Poli, S. (2011). Ternary Ca–Fe–Mg carbonates: subsolidus phase relations at 3.5 GPa and a thermodynamic solid solution model including order/disorder. Contributions to Mineralogy and Petrology, 161(2), 213-227.